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71.
In 30 schizophrenic patients (sixteen of the paranoid subtype, 14 of the nonparanoid) and healthy controls (n = 30) event-related potentials were obtained with a somatosensory reaction-time (RT) version of the "oddball paradigm" by stimulating the right (first run) and the left (second run) median nerve. Variations of P300 amplitude and latency and of RT within the average (30 trials) were studied by fractionating off-line the original averages in three subaverages. After stimulation of the right median nerve oscillations on P300 amplitude and latency were observed. After stimulation of the left median nerve there was a trend toward a decrease of the P300 amplitude that reached significance at the electrode P3 for patients (p = 0.014) and at the electrode P4 for controls (p = 0.025). The P300 latency showed variations for patients and controls. The mean-RT was prolonged across the subaverages only for schizophrenics, reaching significance after stimulation of the right median nerve. Paranoid and nonparanoid schizophrenic patients showed similar results on P300 and RT parameters across the subaverages. These results are discussed in terms of the influence of motivation and task involvement on the P300 amplitude. These could be unspecific factors that account for the habituation of the P300 along the examination. 相似文献
72.
Intraoperative color Doppler recordings, obtained either from the epicardial or transesophageal approach, offer real-time information about the presence and severity of mitral regurgitation at the time of surgery. The technique allows instantaneous evaluation of mitral and tricuspid repair and may offer important information about the postoperative outcome. 相似文献
73.
D M Hays R B Raney W Lawrence M Tefft E H Soule W M Crist M Foulkes H M Maurer 《Journal of pediatric surgery》1982,17(6):812-820
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory. 相似文献
74.
75.
O S Pettengill C S Faulkner D H Wurster-Hill L H Maurer G D Sorenson A G Robinson E A Zimmerman 《Journal of the National Cancer Institute》1977,58(3):511-518
A continuous cell culture line was established from a bone marrow metastasis of small cell anaplastic carcinoma of the lung. The cultures were characterized by light and electron microscopy, and an unusual concentric arrangement of cells was observed, both in sectioned material from the patient's tumor and from the cell cultures. The cells had two types of specialized cell junctions and contained secretory-like granules of the type described in neuroendocrine cells. Lactic dehydrogenase isozyme patterns were the same as those observed in normal human serum, and the karyotype revealed the presence of several marker chromosomes. Vasopressin was present in the cells and secreted into the culture medium in the absence of neurophysin, as shown by the immunoperoxidase technique and radioimmunoassay. Oxytocin was also absent from cells. 相似文献
76.
小牛血去蛋白提取物对胃溃疡患者的疗效评价 总被引:2,自引:0,他引:2
目的:探讨小牛血去蛋白提取物(DCBE)对胃溃疡的治疗作用。方法:选择年龄20~70岁之间,经胃镜检查确诊为活动期胃溃疡的住院患60例。治疗组32例采用静脉滴注DCBE(800mg,qd)和法莫替丁(100mg,bid)治疗;对照组28例采用静脉滴注法莫替丁(100mg,bid)单独治疗。用药2、4wk行胃镜检查,观察自觉缓解症状、时间、愈合率和总有效率。结果:治疗组自觉症状缓解时间明显缩短;给药后2、4wk治疗组及对照组胃镜检查溃疡愈合率分别为78.1%,46.4%及84.4%,71.4%。结论:DCBE能显促进胃溃疡的愈合。 相似文献
77.
Siemer S Uder M Humke U Lindenmeier T Moll V Rüdenauer E Maurer J Ziegler M 《Der Urologe. Ausg. A》2000,39(2):149-153
The importance of ultrasonography in early detection of renal cell carcinoma was analyzed for 1854 patients, who were operated from 1975 to 1997. The 5-year survival rate of all patients amounts to 75%, the 10- and 20-year survival rate was 68% and 64%. While from 1975 to 1986 tumor symptoms like hematuria (30%), abdominal pain (19%) and palpable mass (3%) lead to diagnosis of renal cell carcinoma in 56% of all cases, there were only 26% from 1987 to 1997. 83% of asymptomatical tumors from 1987 to 1997 were accidentally detected by means of ultrasonography in a kidney independent examination. These tumors are significantly smaller (5.5 cm) than the tumors of symptomatical patients (7.8 cm) and show often a significantly lower local tumor stage, a better tumor grade, frequently lymph nodes, which are free of tumor infiltration and more rarely distant metastasis. The 5-year survival rate of patients with incidental tumors, detected by ultrasonography (82%) was significantly better (log rank < 0.001) in comparison with the symptomatical patients (72%). These results verify 1. The effectivity of ultrasonography in early diagnosis of renal cell carcinoma and 2. The advantage of survival on patients with early tumor detection. That's why asymptomatic patients, who selected under risk factors should be examinated by ultrasonography consistently too. 相似文献
78.
Dietmar Springer Liane D Paul Roland F Staack Thomas Kraemer Hans H Maurer 《Drug metabolism and disposition》2003,31(8):979-982
4'-Methyl-alpha-pyrrolidinopropiophenone (MPPP) is a new drug of abuse. It is believed to have an abuse potential similar to that of amphetamines. Previous studies with Wistar rats had shown that MPPP was metabolized mainly by hydroxylation in position 4' followed by dehydrogenation to the corresponding carboxylic acid. The aim of the study presented here was to identify the human hepatic cytochrome p450 (p450) enzymes involved in the biotransformation of MPPP to 4'-hydroxymethyl-pyrrolidinopropiophenone. Baculovirus-infected insect cell microsomes and human liver microsomes were used for this purpose. Only CYP2C19 and CYP2D6 catalyzed this hydroxylation. The apparent Km and Vmax values for the latter were 9.8 +/- 2.5 microM and 13.6 +/- 0.7 pmol/min/pmol p450, respectively. CYP2C19 was not saturable over the tested substrate range (2-1000 microM) and interestingly showed a biphasic kinetic profile with apparent Km,1 and Vmax,1 values of 47.2 +/- 12.5 microM and 8.1 +/- 1.4 pmol/min/pmol p450, respectively. Experiments with pooled human liver microsomes also revealed biphasic nonsaturable kinetics with apparent Km,1 and Vmax,1 values of 57.0 +/- 20.9 microM and 199.7 +/- 59.7 pmol/min/mg of protein for the high affinity enzyme, respectively. Incubation of 2 microM MPPP with 3 microM of the CYP2D6-specific inhibitor quinidine resulted in significant (p < 0.01) turnover inhibition (11.8 +/- 1.6% of control). Based on kinetic data corrected for the relative activity factors, CYP2D6 is the enzyme mainly responsible for MPPP hydroxylation, confirmed by CYP2D6 inhibition studies. 相似文献
79.
Apart from comminuted fractures of the radial head the indication for resection of the radial head is discussed controversially. To evaluate our own results, the hospital notes of 113 patients treated between 1.1.1984-31.12.1994 in our clinic by posttraumatic primary or secondary radial head resection were examined retrospectively. 79 patients were controlled by clinical and radiological examination with an average follow-up of 37.8 months. We examined at 46 patients the influence of additional lesions of the elbow joint on the functional outcome. In 33 patients follow up was done with special regard to the time of resection. Poor results due to the score from Radian and Riseborough especially followed secondary radial head resection (> 14 days after trauma) and in case of additional elbow lesions. We could not observe problems of the wrist joint after radial head resection as described by other authors. According to our own experience primary resection is recommended in case of doubtful reconstruction of the radial head. In these fracture types radial head resection should not be seen as an alternative treatment because of the worse results following secondary resection. 相似文献
80.
Electron microscopic localization of nitric oxide I synthase in the organ of Corti of the guinea pig
U. -R. Heinrich J. Maurer K. Gosepath W. Mann 《European archives of oto-rhino-laryngology》1997,254(8):396-400
Nitric oxide synthase (NOS) activity has been detected previously in the mammalian cochlea at a light microscopic level. Here we present results of electron microscopic analysis for post-embedding immunoreactivity of neural-type NOS I in the cochlea of the guinea pig. Strong enzyme immunoreactivity was identified in the cytoplasm of inner and outer hair cells. Gold-labeled NOS I antibodies were mainly located in electron-dense areas of the cytoplasm, whereas electron-lucent regions of the receptor cells were nearly free from any immunoreactivity. In both types of hair cells anti-NOS I antibodies were also visible in the cuticular plates, hair bundles and nuclei. Further ultrastructural analysis revealed that the submembranous cisternae of the outer hair cells were nearly free from any reaction product, demonstrating that the whole cytoplasm of this hair cell was not immunoreactive. Other NOS I immunoreactivity was identified in the cuticular plates of the inner and outer pillar cells and in the cytoskeletal elements located in the apical parts of Deiter cells, forming the lamina reticularis or in cytoskeletal-containing regions in basal Deiter cells. Anti-NOS antibodies were visible in the nuclei of various cell types. Our findings suggest that nitric oxide produced by NO I synthase in the organ of Corti may act as a modulator of hair cell physiology during the processes of signal transduction with frequence selectivity. 相似文献